what would you do with a killer?

I dont know what the hell is up with all these murderers lately ? especially the child killers ! douchebags throwing their kids off bridges ,burning them ,drowning them ! all sort's of new ways to do it ! shooting your kids because they want to blend in with society ," stupid islamic thing there"and now another murdering scumbag rapist on the loose ! its absolutly crazy anymore ! what would you do if you got ahold of a child killer ?alone ? I think I would beat there ass for awhile before I called the cops ! its a lot less than they deserve , if captured alive they get a trial and when found guilty they get the rest of their life behind bars ,in most cases. They should not be allowed to live after being found guilty ! I watched a great movie once called "Citizen x " a true story about a russian serial killer / pedophile , and the cop who's entire career it took to catch him, it was a long slow movie , but the ending was the best ever ! they showed the man who comitted 53 or so murders{ most of them little girls , it was the only way he could get off} standing in the court room , and they find him guilty ! next scene is him walking down a hall with a cop on either side of him , then they stop , open a door to a small tiled room with a drain in the middle of it and they show the look of absolute horrer on his face as they push him in the room ! next thing is the sound of a gun cocking and then firing ! right to a black screen ! In other country's they deal with murderer's differently! especially child killers ! why pay for them to live the rest of their lives in prison ? when a bullet is much cheaper !